/Engine/Plugins/Experimental/MeshModelingToolsetExp/Source/ModelingEditorUI/Public/STransformGizmoNumericalUIOverlay.h
When true (the default) the panel is positioned by measuring a distance from the bottom of the viewport, and resizing the viewport will keep that distance the same.
WidgetArgsType & bPositionRelativeToBottom &40; bool InArg &41;